CN211325495U

CN211325495U - Anterior reduction internal fixation device for treating Hangman fracture

Info

Publication number: CN211325495U
Application number: CN201922282840.2U
Authority: CN
Inventors: 李广州; 王清; 欧颖
Original assignee: Affiliated Hospital of Southwest Medical University
Current assignee: Affiliated Hospital of Southwest Medical University
Priority date: 2019-12-18
Filing date: 2019-12-18
Publication date: 2020-08-25
Anticipated expiration: 2029-12-18

Abstract

The utility model discloses a front-path reduction internal fixation device for treating Hangman fracture, relating to the technical field of Hangman fracture treatment equipment and comprising a steel plate and a fusion device, wherein the steel plate is connected with the fusion device through screws; the upper part of the steel plate is provided with a bending part inclined towards one side of the fusion device. The utility model discloses a treatment Hangman fracture's anterior way internal fixation device that resets adopts dissection steel sheet and fusion ware to constitute anterior way internal fixation device that resets to fixed action pressurization C2 centrum surface through dissection steel sheet and fusion ware makes C2/3 centrum structure reset easily, easy operation.

Description

Anterior reduction internal fixation device for treating Hangman fracture

Technical Field

The utility model relates to a Hangman fracture treatment equipment technical field, concretely relates to anterior reduction internal fixation device of treatment Hangman fracture.

Background

The axis (second cervical, i.e., C2) is the transitional vertebral body between the occipital neck and the lower cervical spine, and does not have typical vertebral body structure. The anatomical difference between the superior and inferior processes is that the isthmus of the vertebral joint becomes a mechanical lever, which is the stress concentration of the cervical vertebrae at both ends, and the vertebral artery passes through the transverse foramen outside the isthmus of the joint, making it a weak anatomical structure.

Hangman fracture (also called dentata annulus fracture) refers to a fracture that occurs in the area between the upper and lower articular processes of the dentata under the influence of an abrupt force, often accompanied by damage to the surrounding ligaments and the intervertebral disc, and the subsequent instability or dislocation of the vertebral body of the dentata.

Currently, the treatment of the Hangman fracture aims at restoring the physiological sequence of the injured vertebral segment, and the fracture is healed by a proper fixation method. The anterior cervical internal fixation system is a widely used cervical trauma treatment means, and has the advantages of small surgical injury, quick postoperative recovery of patients, help to recover surgical segment sequences, provide better stability, help to implant bone fusion deformity and the like. Therefore, anterior cervical internal fixation systems are also currently commonly used in the treatment of Hangman fractures. However, since the design of the existing internal fixation system is mainly directed to the lower cervical vertebra (C3-7), it faces various risks and problems during the use of the upper cervical vertebra surgery.

SUMMERY OF THE UTILITY MODEL

The utility model provides a to prior art, a treatment Hangman fracture's preceding way internal fixation device that resets is provided with the kink of slope on the steel sheet, makes the steel sheet C2's of laminating more special construction.

The utility model discloses a following technical scheme realizes: the anterior reduction internal fixation device for treating Hangman fracture comprises a steel plate and a fusion device, wherein the steel plate is connected with the fusion device through screws; the upper part of the steel plate is provided with a bending part inclined towards one side of the fusion device.

In the above technical scheme, the structure of the bending part is a trapezoid or triangular structure matching the C2 vertebral body with a small upper part and a large lower part, and the edge turning parts are all in smooth arc transition, so that the structure is more in line with the anatomical structure characteristics of the C2 vertebral body of a human body. The length dimension of kink accounts for about 1/5 of whole steel sheet length dimension, realizes the better anatomical match of steel sheet and C2/3 centrum, and the back is installed to the internal fixation device that resets of way before simultaneously, and the kink plays certain effect of pushing down to the C2 centrum, makes C2 and C3 centrum be close to each other, does benefit to the growth healing that fracture department damaged.

Furthermore, the bending part is a triangular structure with smooth transition at the corner.

Further, the inclination angle of the bending part to one side of the fusion device is 15-25 degrees.

Further, the steel plate is an anatomical steel plate, so that the anatomical steel plate is attached to the structure of a C2/3 vertebral body.

Further, the side surface of the bent part close to the fusion device is provided with a plurality of racks for increasing the friction force between the bent part and the surface of the C2 vertebral body.

Furthermore, the anterior reduction internal fixation device also comprises at least 2 bone nails used for connecting a steel plate and a C2/3 vertebral body, and the steel plate is provided with four grooves distributed in a matrix manner; the bottom surface of the groove is provided with a bone nail hole penetrating through the steel plate, so that the head of the bone nail can be embedded into the groove.

Further, the fusion cage comprises an insertion part and a fixing part which are connected with each other, wherein the insertion part is provided with a bone grafting hole penetrating through the insertion part; the fixing part is provided with a mounting hole, and the steel plate penetrates through the mounting hole and is in threaded connection with the fixing part through a screw.

The steel plate is connected with the fusion cage through the fixing part, and the inserting part is embedded into the interval between the C2 vertebral body and the C3 vertebral body, so that the displacement of the fixing device in anterior reduction is avoided.

Furthermore, a waist-shaped hole extending from the end close to the bending part to the end far away from the bending part is formed in the steel plate; the steel plate is in threaded connection with the fixing portion through the screw penetrating through the waist-shaped hole, so that the steel plate can move up and down along the mounting hole, the position of the steel plate is adjusted, and the steel plate is more attached to the vertebral body structure.

Furthermore, the upper surface and the lower surface of the insertion part are respectively provided with a plurality of bulges or grooves for increasing the contact area between the insertion part and the end plates of the upper vertebral body and the lower vertebral body so as to increase the contact friction force between the insertion part and the end plates of the upper vertebral body and the lower vertebral body and prevent displacement.

The insertion portion is made of PEEK materials, and the fixing portion is made of titanium alloy materials.

Further, the insert comprises an upper surface layer on the upper surface, an intermediate layer and a lower surface layer on the lower surface; the upper surface layer and the lower surface layer are titanium alloy layers made of titanium alloy materials; the middle layer is a PEEK material layer prepared from a PEEK material; the upper surface layer and the lower surface layer are rough surfaces.

Compared with the prior art, the utility model, following advantage and beneficial effect have:

(1) the utility model provides a treatment Hangman fracture's anterior way internal fixation device that resets adopts anatomical steel sheet and fusion ware to constitute anterior way internal fixation device that resets to fixed action pressurization C2 centrum surface through anatomical steel sheet and fusion ware makes C2/3 centrum structure reset easily, the easy operation.

(2) The utility model provides a bent part is arranged at the upper end of the dissection steel plate of the anterior reduction internal fixation device for treating the Hangman fracture, so that the dissection steel plate is more in line with the structural characteristics of the C2/3 vertebral body of a human body, and good dissection matching is achieved; meanwhile, the rack on the surface of the bent part is clamped on the surface of a C2 vertebral body, so that the C2 is pressurized, and the displacement is avoided.

(3) The utility model provides a front way of treatment Hangman fracture internal fixation device that resets adopts steel sheet and the adjustable connection of fusion ware, makes the position of its adjustable steel sheet, makes the better laminating of steel sheet and C2 and C3 centrum.

(4) The fusion part of the anterior reduction internal fixation device for treating the Hangman fracture adopts a three-layer structure of titanium alloy-PEEK-titanium alloy, so that the upper surface and the lower surface of the fusion part are easier to process and coarsen, and the fusion part ensures the performances of more proper elasticity, biocompatibility, strength and the like; the upper surface and the lower surface are roughened and processed with grooves or bulges, so that the contact surface between the fusion part and the end plates of the upper vertebral body and the lower vertebral body is larger, the friction force is larger, and the displacement is not easy.

Drawings

Fig. 1 is a cross-sectional view of an anterior reduction internal fixation device in some embodiments of the present invention;

fig. 2 is a schematic structural view of a steel plate in some embodiments of the present invention;

fig. 3 is a schematic structural view of a fusion cage according to some embodiments of the present invention;

wherein: 1-steel plate, 11-bending part, 12-groove, 13-waist-shaped hole, 2-fusion device, 21-insertion part, 211-upper surface layer, 212-middle layer, 213-lower surface layer, 214-bone grafting hole, 22-fixing part, 221-mounting hole, 3-screw and 4-bone nail.

Detailed Description

The present invention will be described in further detail with reference to examples, but the present invention is not limited thereto.

Currently, the application of an anterior cervical internal fixation system to a Hangman fracture has the following problems:

(1) the Hangman fracture is characterized in that the C2 intertrochanteric fracture is accompanied by C2/3 instability, and because the C2/3 is higher in position and the mandible blocks, effective 'reverse injury pressurization' resistance cannot be exerted, so that the fracture displacement and reduction are difficult;

2. due to the particularity of the C2 structure (the C2 vertebral body is reduced from the C3 vertebral body, and the pivot vertebral body forms a backward inclination angle of about 20 degrees), the existing internal fixation system is not matched with the C2/3 when applied to the C2/3 segment;

3. unstable Hangman fracture requiring surgical treatment is often accompanied by significant forward displacement of the C2 vertebral body, and for the two reasons mentioned above, significant residual deformity after surgery is often caused, and the treatment effect is not ideal. And good biomechanical stability can be achieved by selecting anterior dentate process screw fixation, C2/3 discectomy, intervertebral space bone grafting fusion and steel plate screw internal fixation, and the cost is more complex operation, more operation risks and higher treatment cost.

For unstable Hangman fracture, a posterior C2-C3 pedicle screw internal fixation bone grafting fusion operation can be clinically adopted, but the operation type is faced with the facts that the posterior pedicle screw placing technology is difficult, the operation wound damages more muscles compared with the anterior pedicle screw, and the infection rate is high; some doctors use a fixed fusion operation of the occipital neck, which results in 50% rotation of the cervical spine and more than 20% loss of lateral flexion. In addition, simple posterior C2 pedicle screw fixation is not suitable for cases with combined C2/3 instability, while most of the Hangman fractures requiring surgical treatment are accompanied by C2/3 instability.

Therefore, the utility model provides an anterior reduction internal fixation device for treating Hangman fracture, as shown in figure 1, which comprises a steel plate 1 and a fusion device 2, wherein the steel plate 1 is connected with the fusion device 2 through a screw 3; the upper portion of the steel plate 1 is provided with a bent portion 11 inclined toward the fusion cage 2.

The structure of the bending part 11 is a trapezoid or triangle structure matching the small upper part and the large lower part of the C2 vertebral body, and the edge turning parts are smooth arc transition, so that the structure is more in line with the anatomical structure characteristics of the C2 vertebral body of the human body. The length dimension of the bending part 11 accounts for about 1/5 of the length dimension of the whole steel plate 1, better anatomical matching of the steel plate 1 and the C2/3 vertebral body is realized, and meanwhile, after the front-path reduction internal fixation device is installed, the bending part 11 plays a certain role in pressing down the C2 vertebral body, so that the C2 and the C3 vertebral bodies are close to each other, and the growth and healing of the injury of the fracture part are facilitated.

In some embodiments, the bent portion 11 is a triangular structure with rounded corners.

In some embodiments, the bending part 11 is inclined toward the side of the fusion cage 2 at an angle of 15-25 °. Because the front surface of the C2 vertebral body is reduced relative to the C3 vertebral body and the pivot vertebral body forms a back inclination angle of about 20 degrees, the inclination angle of the bending part 11 is preferably 15-25 degrees, and the fitting effect of the steel plate 1 and the C2/3 vertebral body is not facilitated when the inclination angle is too large or too small.

In some embodiments, the steel plate 1 is an anatomical steel plate 1. The steel plate 1 is not a pure plane steel plate 1 or a rectangular steel plate 1, but has a slightly arc-shaped structure according to the structure of the C2/3 vertebral body, and the four corners of the steel plate are provided with bulges so as to facilitate the installation and the fitting of the bone nail 4 to the C2/3 vertebral body structure.

In some embodiments, the side of the bent part 11 close to the fusion device 2 is provided with a plurality of racks for increasing the friction between the bent part 11 and the surface of the C2 vertebral body, so that the C2 vertebral body is more easily stressed and pressurized, the displacement is reduced, and the fractured C2/3 vertebral body is more easily reduced.

Optionally, the racks on the side surfaces of the bending part 11 are transversely arranged and the number of the racks is 3-5.

In some embodiments, as shown in fig. 2, the anterior reduction internal fixation device further includes at least 2 bone nails 4 for connecting a steel plate 1 and a C2/3 vertebral body, wherein four grooves 12 are arranged on the steel plate 1 in a matrix distribution; the bottom surface of the groove 12 is provided with a hole 4 which penetrates through the steel plate 1.

Optionally, the number of bone screws 4 corresponds to the number of holes of the bone screws 4, also 4. The 4 holes of bone nail are located four angles of steel sheet 1 respectively, are convenient for fixed steel sheet 1.

When the bone nail 4 is connected with the C2 and C3 vertebral bodies, the head of the bone nail 4 is embedded into the groove 12, so that the head of the bone nail 4 is prevented from scratching surrounding human tissues and influencing healing.

In some embodiments, the bone screws 4 are disposed obliquely, and the four bone screws 4 are disposed obliquely in four directions, so that the bone screws 4 close to the bending part 11 and the bone screws 4 far from the bending part 11 form an included angle of 30-40 °, and the C2 and C3 vertebral bodies are pulled to approach each other.

In some embodiments, as shown in fig. 3, the fusion cage 2 comprises an insertion portion 21 and a fixation portion 22 connected to each other, the insertion portion 21 being provided with a bone grafting hole 214 penetrating the insertion portion 21; the fixing portion 22 is provided with a mounting hole 221, and the steel plate 1 passes through the mounting hole 221 and is in threaded connection with the fixing portion 22 through a screw 3. The steel plate 1 is connected with the fusion cage 2 through the fixing part 22, and the inserting part 21 is embedded into the interval between the C2 vertebral body and the C3 vertebral body, so that the displacement of the fixing device in anterior reduction is avoided.

In some embodiments, the steel plate 1 is provided with a waist-shaped hole 13 extending from the end close to the bent portion 11 to the end far away from the bent portion 11; the steel plate 1 is screwed with the fixing portion 22 by a screw 3 passing through the kidney-shaped hole 13. The thickness of the steel plate 1 is in interference fit with the width of the mounting hole 221, when the screw 3 sequentially penetrates through one side wall of the mounting hole 221 and the waist-shaped hole 13 to be in threaded connection with the other side wall of the mounting hole 221, the inner side wall of the mounting hole 221 compresses the steel plate 1, so that the steel plate 1 is not displaced, and the fixation of the steel plate 1 and the fusion cage 2 is realized; meanwhile, due to the arrangement of the waist-shaped holes 13, the position of the steel plate 1 can be adjusted, so that the steel plate 1 can be adjusted according to the difference of C2/3 vertebral bodies of different human bodies, a better attaching effect is achieved, and a better resetting effect is achieved.

In some embodiments, the upper and lower surfaces of the insertion portion 21 are provided with protrusions or grooves 12 for increasing the contact area between the insertion portion 21 and the endplates of the upper and lower vertebral bodies, so as to increase the contact friction between the insertion portion 21 and the endplates of the upper and lower vertebral bodies, thereby preventing displacement.

The insertion portion 21 is made of a PEEK material, and the fixing portion 22 is made of a titanium alloy material. The elastic modulus of the PEEK material is similar to that of cortical bone, the PEEK material has strength and fatigue resistance equivalent to those of metal materials, the sinking risk of the fixing device in anterior reduction is reduced, meanwhile, the PEEK material has good biocompatibility, and artificial bone or autologous bone can be implanted through the bone implantation hole 214.

In some embodiments, the insert 21 comprises an upper surface 211 at an upper surface, an intermediate layer 212, and a lower surface 213 at a lower surface; the upper surface layer 211 and the lower surface layer 213 are titanium alloy layers prepared from titanium alloy materials; the middle layer 212 is a PEEK material layer made of PEEK materials; the upper surface layer 211 and the lower surface layer 213 are rough surfaces.

In the above technical scheme of this application document, the upper surface and the lower surface of insertion portion 21 adopt titanium alloy material, and the centre adopts the PEEK material, and the processing of the upper surface and the lower surface of insertion portion 21 of being convenient for has overcome the high problem of PEEK material processing degree of difficulty, and the centre adopts the PEEK material simultaneously, makes insertion portion 21 have elastic modulus, intensity, stability all to be fit for with the centrum.

The titanium alloy layers on the upper surface and the lower surface of the insertion portion 21 are treated by a sand blasting process to roughen the surface of the titanium alloy layer, so that the contact area between the upper surface and the lower surface and the C2 and C3 vertebral bodies is increased, the friction force is increased, and the insertion portion 21 is not easy to displace.

The above is only the preferred embodiment of the present invention, not to the limitation of the present invention in any form, all the technical matters of the present invention all fall into the protection scope of the present invention to any simple modification and equivalent change of the above embodiments.

Claims

1. An anterior reduction internal fixation device for treating Hangman fracture comprises a steel plate (1) and a fusion device (2), wherein the steel plate (1) is connected with the fusion device (2) through a screw (3); the method is characterized in that: the upper part of the steel plate (1) is provided with a bending part (11) which inclines to one side of the fusion device (2).

2. The anterior reduction internal fixation device for treating Hangman fracture according to claim 1, wherein: the bending part (11) is a triangular structure with smooth transition at the corner.

3. The anterior reduction internal fixation device for treating Hangman fracture according to claim 2, wherein: the inclination angle of the bending part (11) to one side of the fusion device (2) is 15-25 degrees.

4. The anterior reduction internal fixation device for treating Hangman fracture according to claim 1, wherein: the steel plate (1) is an anatomical steel plate (1).

5. The anterior reduction internal fixation device for treating Hangman fracture according to claim 1, wherein: the side face of the bending part (11) close to the fusion cage (2) is provided with a plurality of racks.

6. The anterior reduction internal fixation device for treating Hangman fracture according to claim 1, wherein: the bone nail fixing device is characterized by further comprising at least 2 bone nails (4), wherein four grooves (12) are formed in the steel plate (1) in a matrix distribution; the bottom surface of the groove (12) is provided with a bone nail (4) hole penetrating through the steel plate (1).

7. The anterior reduction internal fixation device for treating Hangman fracture according to any one of claims 1-6, wherein: the fusion cage (2) comprises an insertion part (21) and a fixing part (22) which are connected with each other, wherein the insertion part (21) is provided with a bone grafting hole (214) which penetrates through the insertion part (21); the fixing portion (22) is provided with a mounting hole (221), and the steel plate (1) penetrates through the mounting hole (221) and is in threaded connection with the fixing portion (22) through a screw (3).

8. The anterior reduction internal fixation device for treating Hangman fracture according to claim 7, wherein: the steel plate (1) is provided with a waist-shaped hole (13) extending from the end close to the bending part (11) to the end far away from the bending part (11); the steel plate (1) is in threaded connection with the fixing part (22) through a screw (3) penetrating through the waist-shaped hole (13).

9. The anterior reduction internal fixation device for treating Hangman fracture according to claim 7, wherein: the upper surface and the lower surface of the insertion part (21) are provided with a plurality of bulges or grooves (12).

10. The anterior reduction internal fixation device for treating Hangman fracture according to claim 9, wherein: the insert (21) comprises an upper surface layer (211) on the upper surface, an intermediate layer (212) and a lower surface layer (213) on the lower surface; the upper surface layer (211) and the lower surface layer (213) are titanium alloy layers prepared from titanium alloy materials; the middle layer (212) is a PEEK material layer prepared from a PEEK material; the upper surface layer (211) and the lower surface layer (213) are rough surfaces.